There are about five hundred million messages sent around the world per month by estimation. Just as e-mail to computer, short messages are also popular to user of cellulous phone. More particularly, the WAP (wireless application protocol) combining the service of mobile network and Internet skill also provides value-added data service for cellulous phone. Therefore, cellulous phone user can send textual message or graphic message to his friend when verbal conversation is not convenient for him.
However, text input is tedious work for cellulous phone user because extremely limited keys are provided on the keypad of the cellulous phone.